DNA compaction in a protein-DNA complex such as the arrangement of DNAs on a chromosome is a very important subject of biochemical research. Compaction by organic micromolecules and inorganic ions is also an important subject of research relevant to transfection [e.g. Yoshikawa, Y. et al., FEBS Letters, 1996, vol. 396, 71–76; Behr, J-P, Acc. Chem. Res., 1993, vol. 26, 274–278; etc.].
The present invention has for its object to provide a novel means for DNA compaction.